Shaft seal



' C. T. HAYE-S Sept. 16; 1952 SHAFT SEAL Filed Oct. 6, 1948 2 SHEETS-SHEET 1 NGE S mw Illlll SePt 1,6 1952 c. T. HAYES 2,610,872

v SHAFT SEAL Filed oct. e, 194e 2 sHEETs--smw 2 FIG 3 Patented Sept. 16, 1952 UNlrEo STAT-ss TSHAFT SEAL. Charle's T. Jiayes,v1enosha,"`Ws., assign-or 7to Dynamatic Corporation, Kenosha, Wis., alcorporationl'of Delawarev Asplieaiion october. s, 19.4s,seria1.-N.5s;n4s

l.This invention'relates' generally to v-rotary shaft seals,` "and'more .particularlyto Water seals :for

:.4 claims. (o1.` ass-i1) compressedbronze'or-similarfmetal. The inter# naldiameter 'of the sleeve II is suchl thati'it'has a.-running l'flt`with respect to shaft '1, the'shaft being .ground to Ya -journalnish throughout'th'e portion of 'its 'periphery engaged `by the sleeve.v

. The lsl'eeve II .is coi-icentricall-y flicedwithin the iluidv from one vside of the' seal to the other; the

provision of aself-lubricating, low-friction shaft seal :of Vthe class described which allows rotation of fthe shaft at high speeds without overheating of theiseal; the :provision of a shaft seal of this classadapted forl operation for verylong periods of timev withoutwearingto Vthe point where leakagev will occur; Athe Aprovision 'of a .shaft seal such ascdescribed:adapted-to .accommodate eccentr'cities of the ishait; :and the provision of a shaft seal suchas described'wlhich'i's of simplified .con-v struction, economical to manufacture, easy to install and reliable in operation. .Oth'er'objectsk will bein part apparentzrand V'in part pointed out hereinafter.. The invention .accordingly :comprises the 1ele` ments and :combinations 'of elements,'ffeaturesfof construction, and 'arrangements of parts which will be exemplified in thestructureshereinafter described, and tthe scopeof vthe application 'of which will be indicated in thefolilowing claims. In Vthe accompanyingdrawings, iin '-whichlsew' eral of `various possible embodiments .ci the i-nvention are illustrated, `Fig. 1 iis 'a longitudinal section illustrating a rst embodimentzofitheinvention; f

Fig.` 2 isfa similar *sectionA illustrating; embodiment;

Fig. 3 is a similar embodiment; and

Fig. 4 'is'an end View oftFig. 3 as viewed .from the right, with .parts brokenaway iandishownA in section.

Similar reference characters indicate corre,-l sponding parts throughout the several views fof the drawings. Y

.Referring to Fig. l, there is shownlat han end wall yof .-thefhousing of an eXemplary'Water-cooled eddy-current .dynamometen coup1ingclutchfcr the like. v.lin this wall is a bearingaperture f3v vin the outer end of whichiisa ballzbearing-.asselnbly 5. A shaft 'I .extends through .the aperture f3 and is. journalled in the lball bearing. Numeral ffggenerally designates .ashaft :seal .of this-invention for preventing vleakage .ofwater fromiwithin the: housing through aperture :135.to the :bearing As illustrated, y'shaft "seal 9 comprises :a rigid, porous sleeve IIof oil-impregnated sintered and isecond Lsection .illustrating a third'- central aperture 'I3 of a flexible'iand yresilient closure member `ordiaphragm I 5, comprising a disc of v'synthetic oil-resistantrubber -or other suitable flexible material. AsA illustrated, the sleeve is `formed `with Yan -outwardly extending ange l on .its end remot'effrom bearing-E.- A collar I9 1press-fitted on sleeve II compressesagainst ilange .I1 the 'inner annular portionof diaphragm I5. 'This fixes thegsl'eeve I I in vthe central opening in the diaphragm to 4provide `"a seal Vagainst vlealnage rbetween the diaphragm 'and' thesleeve. I

tion of thel diaphragm against the 'wall I- for sealing purposes.

A sealing ring 25 having at one endan outwardly yextending flange 21 'is 'fixed on 'shaft 1 in position lfor -a running sealing engagement Yof i the'interior of vsleeve II.

The diameter of ange '21'is somewhatgreaterA the end face of flange 21 with the end faceof flange I'l of sleeve I I. "The ring 25 may-be press-` tted on the'sha'ft or secured thereon 'in 'any othersuitablewa'y so as vto be `rotatable vwith'the shaft yand to prevent leakage between the'ring and the shaft. The sealing 'ring 25 is located in suchposition as to distort the flexible diaphragm I5 toward vthe bearing 5. v'The diaphragm |15 therefore biases -sleeve II toward ring 25 so that the -sleeveis pressed lightly against the ring. This provides a radially directed running tseal 'at the contacting faces of flange I1 of sleeve II and ange 21 o the sealing ring 25. This vprevents Vfluid from passing between the flanges than the diameter ofilange I1. VHence flange?! acts 'as a centrifugal thrower or `slinger `to throw uid outward fromV sealing ring v25 upon rotation ofthe shaft. zThis tends to prevent fluid .from reaching the seal between vthe contacting faces of anges ill'lfland121.. 1

It will be Lclear from the 'abo-'ve 'that shaft sea'l Q-eftectively'-preveits `leakage of fluid through grsszlllr orrlcs aslogsvz aperture 3 from the interior of the housing to bearing 5. Fluid tending to reach the seal at the contacting faces of flanges I1 and 21 is thrown outward by the flange 21. Should any fluid escape the centrifugal action of flange 21, all if not most of it is prevented from flowing to the interior of sleeve II at the running seal between rthe contacting faces of flanges I1 and 21. If, however, any fluid should reach the interior of sleeve I I, it will be prevented from flowing along the periphery of shaft 1 to the bearing by the running seal between the interior surface of sleeve II and -the periphery of thevshaft 1.

The fluid cannot leak out through the central opening I3 in diaphragm I5 nor between the periphery of the diaphragm I5 and the wall I of the housingr because the compressed portions of the diaphragm act as packings to prevent leakage.

Since the sleeve II is formed of oil-impregnated. material, the sealis self-lubricating and operates with little friction between the interior of sleeve I I and the periphery of shaft 1, and between-the contacting sealing faces of flanges I1 and,|9. Since sleeve I I is carried within the flexible diaphragm I5, `it is floatingly -mounted for radial movements to accommodate any eccentricities of shaft 'I resulting from inaccurate journalling of the shaft or other causes. Also, since sleeve II is floatingly mounted bymeans of the flexible diaphragm I5, -there is little or no bearing load upon the sleeve. vThis permits shaf-t 1 to be rotated at very high speeds without overheating ofthe seal and permits operation of the shaft for very long periods of time without undue wear between rubbing surfaces of the parts of the seal. The above points of advantage are particularly useful in connection with the large shafts (often several inches in diameter) employed on dynamometers and the like of substantial sizes.

.l Sealing ring may be omitted, although the seal is improved by its use. A satisfactory seal may be obtained bythe use of oil-impregnated sleeve without sealing ring 25 since use of the self-lubricating sleeve permits reduction of running clearance of the interior of the sleeve and the periphery of shaft 1 to the degree where an effective fluid-tight seal is providedV between these parts.

Fig. 2 illustrates an arrangement embodying two seals 29 and 3| of the same general type as the seal of Fig. 1 in series, with a drain 33 between the seals for any leakage that may occur through the inside seal 3|. In Fig. 2, numeral 35 designates the end wail of the housing of a watercooled dynamometer, eddy-current coupling, clutch or the like, having a longer bearing aperture 31 than the aperture 3 in Fig. 1. Ball bearing assembly 5 is fitted in the outer end of bearing aperture 31. Shaft 1 extends through the aperture 31 and is journalled in the ball bearing. The aperture 31 is counterbored from its inner end, as indicated at Y39, -to provide a shoulder 4I at the inner end of the counterbore.

. lSeal 29 is' located at the inner end `of the counterbore 39. It comprises an oil-impregnated sleeve 43 like sleeve II flxed in the central opening 45 of a flexible diaphragm 41 like diaphragm I5 by means of a collar 49. Sleeve 43 has an end flange 5| on its end remote from bearing 5. Collar 49 also has an end flange 53 and is pressfitted on the sleeve in such manner as to compressA the inner annular portion of diaphragm 41 surrounding the central opening therein between flange 53 and the flange 5I on sleeve l43. A sealing ring 55 like sealing ring 25 of Fig. 1 is xed on shaft 1 in position for running sealing engagement of the end face of flange 51 at one end of the ring with the end face of flange 5| of sleeve 43. Ring 55, however, is not necessarily located in such position as to distort the flexible diaphragm 41 toward bearing 5 as in Fig. 1, inasmuch asthe sleeve 43 is biased toward ring 55 by a coil compression spring 59.

Spring 59 surrounds the collar 49 and reacts against the flange 53 of the collar from an annular cage 6| surrounding shaft 1. The cage 6| is of generally cup-shape, having an aperture 63 in its bottom accommodating shaft 1 and an outwardly extending rim 65 which abuts the shoulder 4|. The outer peripheral portion of diaphragm 41 abuts rim 55 and is compressed by a ring GTiltted in the counterbore 39 and retained in place by screws 69 extending through the ring 61 and threaded into the wall 35 of the housing.

Shaft seal 3| is located at the outer end of counterbore 39. It comprises an oil-impregnated sleeve 1I like sleeves II and 43 flxed in the central opening 13 of a flexible metallic diaphragm 15 by means of a collar 11 like collar 49. Sleeve 1I has an end flange19 like flanges I1 and 5I on its end remote from the bearing 5. Collar 11 also has an Y end flange 8| and is press-fitted on the sleeve 1I in such manner that the inner annular portion of the flexible metallic diaphragm 15 is clamped between the flanges 19 and 8| for sealing pur-A poses. A sealing ring 83 having an end flange 85 is fixed on shaft 1 in position for engagement of Ithe end face of flange 85 with the end face of flange 19 of the sleeve 1|. As in the case of the shaft seal 29, it is not necessary that the ring 83 distort flexible diaphragm 15, inasmuch as sleeve 1| is biased toward ring 83 by a coil compression spring 81.

Spring 81 reacts against the flange 8| of collar 1I from an annular cage 9| similar to the cage 6I of seal 29. Cage 9| has an aperture 93 in its bottom through which shaft 1 extends, and has a peripheral rim 95 which is bent around the periphery of flexible metallic diaphragm 15. The rim 95 abuts the end of ring 61 and is ilxed in place by the screws 69, which extend through rim 95 and then through the ring 61. The screws are threaded into wall 35 suiciently'to clamp the rim sealingly against the end of the ring 61.

, 25 in Fig. 1.

Flanges 51 and 85 of the sealing rings 55 and 83 are of greater diameter than flanges 5| and 19 of the sleeves 43 and 1| soas to constitute slingers in-the same-manner as flange 21 of sealing ring It will be understood that each of seais 29 and 3| function in the same manner and have the same advantages as the seal 9 of Fig. 1. Should any fluid leak past seal 3| it will be prevented from leaking out to bearing 5 by seal 29, and will drain out through drain 33, which passes through wall 35 and ring 61. This leads from the space between the two seals to the exterior of the apparatus. v

If a seal such as Vshown in Fig. 1 is employed under conditions wherein any oil that may be exuded from the oil-impregnated sealing sleeve II maybe washed away before it is re-absorbedl by the sleeve, the sleeve may slowly lose its oil and ultimatelybecome dry of oil. For example, if the seal is employed under conditions where it is partially'or completely submerged in water oil, which is floated away with the water in which the seal is submerged before it'can be re-ab-.

sorbed. When the sleeve, under such conditions,

becomes dry of oil, its rate of wear'increases rapidly and it no longer provides a satisfactory seal. To adapt the seal of Fig. 1, for example, for use under such circumstances, it may be modied as illustrated in Figs. 3 and 4 to include a lubricator for maintaining the oil content of the oil-impregnated sealing sleeve substantially constant over a considerable period despite washing away of exuded oil or loss of oil due to other factors.

As shown, the seal of Figs. 3 and 4 is substantially the same as the seal shown in Fig. l, with similar reference characters indicating corresponding parts, with the exception that the oilimpregnated sleeve, designated lli in Figs. 3 and 4, has a smaller iiange ill than the flange l'l of sleeve il of Fig. l, and is iixedly sealed in the central opening in diaphragm l5 between a separate ilange |18 press-iitted on the sleeve against the ange l Il and a special lubricator collar H9 Whichrtakes the place of collar i9 of Fig. 1. The collar H9 is formed with a hub i2i which is press-fitted on the sleeve Ill and compresses against the collar H3 the inner annular portion of diaphragm l5. On the end of the hub 121 remote from the diaphragm is an outwardly extending flange 123. 1n the face of this nange toward the diaphragm is an annular groove cr recess |25 immediately surrounding the hub. Fitted in the groove 12d and surrounding the hub is a ring or wick 121 of felt or similar absorbent material which is initially saturated with lubricating oil. The ring |27 is held in the groove by the diaphragm l5. rIhe hub l2! has a series of small radial apertures E29 therethrough leading from the oil-saturated felt ring l2? to the periphery of the sleeve l H. The arrangement is such that oil is supplied from the ring 12T to the sleeve through the holes 129 by capillary action to replenish oil lost by the sleeve. An oil hole |31 may be provided in the Wall l of the housing in which the seal is mounted to provide for re-saturating felt ring 121 with oil at infrequent intervals, if necessary.

It will be understood that cylindric bellowstype closure members may be substituted for the flat bellows-type diaphragm closure members disclosed herein, and the terms closure member and diaphragm are intended to include various bellows.

It will be understood that either of the constructions shown in Fig. 2 may be used singly. Also, of the four forms of the sealing portions of the invention shown in Figs. l, 2, and 3 any one may be used in multiple.

In View of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

l. For use in a shaft seal, a ilexible closure member having an opening, an oil-impregnated sleeve oi? porous material iixed concentrically within the opening in the member in sealed relation with respect to the member, the sleeve being adapted for a self-lubricating running seal between its interior and the periphery of a shaft extending through the sleeve, and lubricating means including an absorbent wick adapted to be saturated with oil carried by the sleeve for supplying oil thereto to make up loss of oil from the sleeve.

2. For use in a shaft seal, a flexible diaphragm having a central opening, an oil-impregnated sleeve of compressed sintered metal fitted in the central opening in the diaphragm and sealed with respect thereto, a collar xed on the sleeve having a recess, oil-saturated absorbent material in said recess, said collar having an aperture leading from said recess to the sleeve for supplying oil from said material to the sleeve to make up loss of oil from the latter.

3. For use in a shaft seal, a exible diaphragm having a central opening, an oil-impregnated sleeve of rigid porous material having a flange, said sleeve being fitted in the central opening in the diaphragm with its flange abutting the diaphragm, and a collar tted on the sleeve and compressing the portion of the diaphragm surrounding the sleeve against the flange, said collar having an annular groove therein, a ring of oil-saturated absorbent material fitted in said groove, said collar having apertures leading from said groove to the periphery of the sleeve for supplying oil from said oil-saturated ring to the sleeve to make up loss of oil from the latter.

4. lFor use in a shaft seal, a flexible diaphragm having a central opening, an oil-impregnated sleeve of compressed sintered metal having a flange, said sleeve being iitted in the central opening in the diaphragm with its flangev abut--y ting the diaphragm, and a collar having a hub fitted on the sleeve compressing the portion of the diaphragm surrounding the sleeve against said flange, an outwardly extending iiange on the end of the hub remote from the diaphragm having an annular groove immediately surrounding the hub and facing toward the diaphragm, and a ring of oil-saturated absorbent material fitted in said groove, said hub having a series of small radial holes therethrough leading from the groove to the periphery of the sleeve.

CHAS. T. HAYES.

REFERENCES CITED The following references are of record in the nie of this patent:

UNITED STATES PATENTS Number Name Date 1,158,719 Reynolds Nov. 2, 1915 Y 1,170,285 Lachmann Feb. 1, 1916 1,789,978 Hull Jan. 27, 1931 v 1,930,312 Greenhoe Oct. 10, 1933 2,080,403 Homan May 18, 1937 2,209,855 Smith et al. July30, 1940 2,354,478 Reinhardt et al. July 2,5, 1944 2,382,960 Compton et al. Aug. 2l, 1945 2,440,155 Peterson et al. Apr. 20, 1948 FOREIGN PATENTS Number Country Date 484,623 Germany of 1929 518,339 Great Britain of 1940 

